1. Field of the Invention
The present invention is related to a method for producing metal with a sponge structure of which the shapes and sizes of the pores are controllable, and especially to a method for producing porous sponge like metal, the physical and mechanical feature and quality of the sponge like structure of the metal can be changed by this method, and the shapes and sizes of the pores of the shaped metal structure can be controlled thereby, therefore, control of a single nature or a compound nature of specific weight, density, strength, toughness, fire-proof capability, sound insulation, heat insulation and magnetic wave disturbance-proofing etc. can be gotten in order to make the metal a metallic material of special structure.
2. Description of the Prior Art
A conventional processing technique to form a metal into the structure of a sponge has been used mainly taking aluminum as its metallic material, aluminum has the features of lightness and good heat-sinking capability, it is beneficial to being founded into an aluminum porous board (it is called in abreviation AP), the board is structurally formed to have aluminum alloy oxide thin film and a lot of foams, it is thereby capable of insulating conducting of heat, sound wave and electromagnetic wave etc., and can improve the original lightness and heat sinking capability of the aluminum material, so that it can become a construction material having the features of fire-proofing, sound insulation, heat insulation or magnetic wave disturbance-proofing etc.
However, the technique for casting the conventional aluminum porous board is not quite ideal, this is because that it is difficult to be controlled. in size, shape, volume, density and strength of its foams, and can only be formed the foam structure of the aluminum board with smaller unit areas, thereby, the foamed aluminum board made can only have limited capability of fire-proofing, sound insulation, heat insulation or magnetic wave disturbance-proofing etc. which is hard to be improved; any more, and in manufacturing of the conventional foamed aluminum board, it must expend very high cost for the equipment for continuous casting and foaming, and this is a technical impediment which is extremely troublesome, it is hard to control the size, density and independency of each foam of the porous structure manufactured, in this view, the physical and mechanical feature and quality of the porous structure is inferior, and this is the defect thereof.
Moreover, the technique for casting the conventional porous aluminum board (if it is not independently foamed or sponge like) does not suit other alloys, and there is not any technique for manufacturing porous sponge like structure on other alloys of high melting points or low melting points other than the porous aluminum boards in the markets. This is a pity by virtue that if the physical and mechanical feature and quality of these alloys other than aluminum can be made to manufacture a porous sponge like (or independent foamed) structure, the original materials can have their specific weight lowered, and have their single or compound nature of compression strength, fire-proofing capability, sound insulation, heat insulation or magnetic wave disturbance-proofing etc. improved. While such a technique has still not yet been developed in the markets.